Question

(a) What are conductors?
(b) If $3000$ electrons are added to a metal sphere, what is the charge acquired by it?

Answer 1

Hint: In the first bit we have to define conductors, which allow the current to flow through it. Now for the second bit we know the charge of one electron is $ - 1.6 \times {10^{ - 19}}C$ where the SI unit of charge is coulomb. Using this relation between electron and charge we can find the solution of the given problem.

Complete step by step answer:
(a) We can define an electric conductor as the materials that allow electricity to flow through it. The flow of electrons through a conductor is called electric current and the force that is required to make the current to flow through the conductor is called the voltage. Hence this property of the conductor that allows the current or we can say allow to conduct electricity is called the conductivity of the materials.Humans are good conductors of electricity, that's why we get electric shocks.

(b) As per the problem we need to find the charge acquired by the metal sphere when an amount of electrons is added to it. We know that one electron is equal to $ - 1.6 \times {10^{ - 19}}C$.Now we need to calculate the charge due to $3000$ electrons.Hence,
$3000$ Electrons is equals to,
$3000\,{\text{electrons}} = 3000 \times \left( { - 1.6 \times {{10}^{ - 19}}C} \right)$
$ \Rightarrow 3000\,{\text{electrons}} = - 4800 \times {10^{ - 19}}C \\
\therefore 3000\,{\text{electrons}}= - 4.8 \times {10^{ - 16}}C$

Therefore if $3000$ electrons are added to a metal sphere, then $ - 4.8 \times {10^{ - 16}}C$ charge is acquired by it.

Note: Remember some of the examples of conductors are copper, gold and our planet is also a good conductor. Note the negative electron consists of negative charge while a proton consists of positive charge. Both electrons and protons are equal in magnitude but their charges are opposite.